Session management apparatus, communication system, and session clear-out method

Abstract

Session management means holds session information concerning sessions for fixed terminals and sessions for mobile terminals including type information indicating a terminal type and status information indicating the status of communication. Session clear-out means disconnects a session the type information for which indicates a mobile terminal and in which communication has not been performed for a time period longer than or equal to a first monitoring time period, on the basis of the session information held in the session management means.

1. A session management apparatus comprising:
 a session management unit that holds, for a session for a fixed terminal and for a session for a mobile terminal, session information including type information indicating a terminal type and status information indicating the status of communication; and 
 a session clear-out unit that disconnects, on the basis of the session information held in the session management unit, a session for which the type information indicates a mobile terminal and in which no communication has been performed for a time period longer than or equal to a first monitoring time period, 
 wherein the session clear-out unit further disconnects a session the type information of which indicates a fixed terminal and in which no communication has been performed for a time period longer than or equal to a second monitoring time that is period longer than the first monitoring time period. 
 
     
     
       2. The session management apparatus according to  claim 1 , wherein
 the status information is updated when communication is performed; and 
 the session clear-out unit determines on the basis of update status of the status information whether no communication has been made for a time period longer than or equal to the first monitoring time period. 
 
     
     
       3. The session management apparatus according to  claim 2 , wherein
 the status information is time information indicating the time at which the latest communication has been performed; and 
 the session clear-out unit determines on the basis of the time indicated by the time information and the current time whether no communication has been performed for a time period longer than or equal to the first monitoring time period. 
 
     
     
       4. The session management apparatus according to  claim 1 , wherein the session clear-out unit extracts at every predetermined determination interval a session the type information of which indicates a mobile terminal and in which no communication has been performed for a time period longer than or equal to the first monitoring time period. 
     
     
       5. The session management apparatus according to  claim 1 , wherein there are a plurality of cells to which the fixed terminal or the mobile terminal can be connected and the monitoring time period for determining whether a session is to be disconnected or not is set for each of the plurality of cells. 
     
     
       6. The session management apparatus according to  claim 1 , wherein the status information comprises time information indicating a time at which a last communication was performed. 
     
     
       7. A communication system comprising:
 a fixed terminal connected to a core network through a radio access network; 
 a mobile terminal connected to the core network through the radio access network and performs communication while a session is established, in such a manner that the time during which no communication is performed does not exceed a predetermined maximum communication interval; and 
 a session management apparatus which holds, for a session for the fixed terminal and for a session for the mobile terminal, session information including type information indicating a terminal type and status information indicating the status of communication and disconnects, on the basis of the session information, a session for which the type information indicates a mobile terminal and in which no communication has been performed for a time period longer than or equal to a first monitoring time period, 
 wherein the session management apparatus further disconnects a session the type information of which indicates a fixed terminal and in which no communication has been performed for a time period longer than or equal to a second monitoring time period that is longer than the first monitoring time period. 
 
     
     
       8. The communication system according to  claim 7 , wherein
 the status information is updated when communication is performed; and 
 the session management apparatus determines on the basis of update status of the status information whether no communication has been made for a time period longer than or equal to the first monitoring time period. 
 
     
     
       9. The communication system according to  claim 7 , wherein
 the status information is time information indicating the time at which the latest communication has been performed; and 
 the session management apparatus determines on the basis of the time indicated by the time information and the current time whether no communication has been performed for a time period longer than or equal to the first monitoring time period. 
 
     
     
       10. The communication system according to  claim 7 , wherein the session management apparatus extracts at every predetermined determination interval a session the type information of which indicates a mobile terminal and in which no communication has been performed for a time period longer than or equal to the first monitoring time period. 
     
     
       11. The communication system according to  claim 7 , wherein there are a plurality of cells to which the fixed terminal or the mobile terminal can be connected and the monitoring time period for determining whether a session is to be disconnected or not is set for each of the plurality of cells. 
     
     
       12. A session clear-out method comprising:
 holding, for a session for a fixed terminal and for a session for a mobile terminal, session information including type information indicating a terminal type and status information indicating status of communication; and 
 disconnecting, on the basis of the session information, a session for which the type information indicates a mobile terminal and in which no communication has been performed for a time period longer than or equal to a first monitoring time period; and 
 disconnecting a session the type information of which indicates a fixed terminal and in which no communication has been performed for a time period longer than or equal to a second monitoring time that is period longer than the first monitoring time period. 
 
     
     
       13. The communication system according to  claim 7 , wherein the status information comprises time information indicating a time at which a last communication was performed.